I’ve done this several times over the years – be sure that the speaker system you go into can handle the extended range of the harp without distortion or overloading particularly around the 5th octave – couple of the places I was at had very low quality speakers in the ceiling and could not take the range of the harp – definitely try to have a sound check before the event – I prefer transducer pickups so that you don’t pick up ambient noise – also many of them have a pre-amp with volume and tone controls that you can adjust during the job without having to find someone to adjust the PA system controls – if you can set it up, the advantage is that you get really nice even coverage of the event without blasting in one area – my current amp has a line out which can send my sound to their PA which is also a nice addition – have fun